English

Linkedness and ordered cycles in digraphs

Combinatorics 2007-05-23 v1

Abstract

The minimum semi-degree of a digraph D is the minimum of its minimum outdegree and its minimum indegree. We show that every sufficiently large digraph D with minimum semi-degree at least n/2 +k-1 is k-linked. The bound on the minimum semi-degree is best possible and confirms a conjecture of Manoussakis from 1990. We also determine the smallest minimum semi-degree which ensures that a sufficiently large digraph D is k-ordered, i.e. that for every ordered sequence of k distinct vertices of D there is a directed cycle which encounters these vertices in this order.

Keywords

Cite

@article{arxiv.0704.0211,
  title  = {Linkedness and ordered cycles in digraphs},
  author = {Daniela Kühn and Deryk Osthus},
  journal= {arXiv preprint arXiv:0704.0211},
  year   = {2007}
}